Use these in airplanes to save some weight?

We usually use two independently switchable batteries (at least I do) so the self-protection low voltage feature may not be a problem.

http://eetweb.com/power-supplies/lithium_batteries_3411/

http://4xspower.com/products/

Perry Mick

That is the way Mike set up the RV4. Is 28 AmpHr (both batts.)
enough for starting?

Paul Lamar